World looks for answers

When the space shuttle Challenger exploded on liftoff 17 years and four days ago, it was seen as a great tragedy for the US. But the destruction of the space shuttle Columbia, as it neared its final touchdown on Saturday morning, is likely to be seen as an international tragedy, even beyond the fact that the first Israeli astronaut died in the accident.

NASA and government officials were scrambling to discover the reason that the orbiter broke apart in flames over Texas. Seven astronauts, six Americans and one Israeli, died in the incident. The shuttle disappeared around 9 a.m. EST, about 15 minutes before it was scheduled to land at Cape Canaveral in Florida. Residents of eastern Texas reported hearing a "window-rattling boom" and seeing white smoke plumes in the sky.

"A contingency for the space shuttle has been declared," Mission Control repeated again and again as it was unable to reestablish communication with the shuttle.

In a late afternoon briefing Saturday, NASA shuttle director Ron Dittemore said the first indication of trouble came a few minutes before 8 a.m. CST when Mission Control reported the loss of temperature sensors in the hydraulic systems on the shuttle's left wing. A few minutes later, they saw a loss of tire pressure indicators in the tire well of the left wheel. Dittemore said there was then an indication of excessive structural heating on the left side. Ground control then lost communication with the shuttle.

Dittemore said that he and his teams would be poring over the data and feedback for "24 hours a day for the foreseeable future."

Addressing the nation on TV, President Bush said that "this day has brought terrible news and great sadness to our country." Mr. Bush said the astronauts knew the dangers and faced them willingly. "Their courage, darling and idealism will mean that we will only miss them all the more.

"The same Creator who names the stars also knows the names of the seven souls we mourn today," said Bush. "The crew of the shuttle Columbia did not return safely to Earth; yet we can pray that all are safely home."

Saturday morning, immediate speculation centered on whether an incident that took place when the shuttle launched on Jan. 16 might have played a role in the breakup. Shortly after Columbia lifted off, a piece of insulating foam on its external fuel tank came off and was believed to have hit the left wing. But, on Friday, the lead flight director in Mission Control assured reporters that engineers had concluded that if the wing had been hit, the damage would have been minor and would have posed no threat to the crew.

There are several astronauts on the International Space Station who were due to come home in March on a US shuttle, according to a NASA official. It is unlikely that mission will take place on time, the official said. The astronauts were resupplied recently by a Russian spacecraft and could return via a Soyez capsule that is part of the station. Or another Russian space mission could be launched in time to bring the astronauts back to Earth, if needed. They have enough supplies to last until the end of June, NASA officials said.

When the Challenger was destroyed in 1986, the US operated its space program on its own. But over the past decade, nations that had been interested in running their own space programs - Canada, Japan, and several European nations - had decided to abandon their own efforts and join with the US's manned space flight efforts. The question that will be faced in the coming weeks is how this tragedy will affect the global manned space program. Other nations were already upset that the US had decided to scale back its participation in the international space station. Now, with only a remaining fleet of three orbiters, and little chance that new shuttles will be built on the current model following Saturday's tragedy, the likelihood of further delays is even greater. Canada and Japan already have hardware that is overdue to be delivered to the space station.

Currently, the US, Russia and China operated manned programs. Although China has not yet sent a man or woman into space, Chinese officials are planning to launch a manned flight before the end of the year, which could catapult the Asian nation into the lead in space exploration.

Columbia, which was NASA's oldest shuttle, has flown 28 missions since its launch 22 years ago. It had been through at least one refurbishing. When Challenger was destroyed, NASA grounded the entire fleet for almost three years. But the Challenger disaster was seen as a very clear design flaw.

The flight included the first Israeli astronaut, Col. Ilan Ramon. Soon after the incident was reported, some media commentators raised the possibility that the flight was a victim of a terrorist act. But officials from the new department of Homeland Security almost immediately said there was no evidence of terrorism.

"At this time we have no indication that the mishap was caused by anything or anyone on the ground," NASA Administrator Sean O'Keefe said in a press conference Saturday afternoon.

"They dedicated their lives to pushing the scientific challenges for all of us on earth," he said. The NASA family will "never be able to get over the loss of this valiant crew," he added.

The accident was felt particularly hard in Israel. Much of the nation was watching TV coverage of the planned shuttle landing, and instead watched breaking news reports from the US that the shuttle had been lost on reentry. Col. Ramon, a veteran of two wars, was the son of a Holocaust survivor and was seen as a hero by his nation. One of the items he took on the flight was a palm-sized Torah scroll that had been kept safe by a Jewish boy in a concentration camp during World War II.